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Traditional wisdom holds that it’s not so much what you say to your dog as how you say it that counts — that tone, in other words, is everything.

But scientists in Hungary say dogs may understand more words than we think — and that it takes a combination of positive words and a positive tone for their brains to register a pleasurable reaction.

“Both what we say and how we say it matters to dogs,” said Attila Andics, a research fellow at Eotvos Lorand University in Budapest.

MRI readings conducted in the study showed the right hemisphere of dogs’ brains react to intonation, while the left hemisphere reacts to the meaning of words — as is the case with humans.

Their paper was published in this week’s issue of the journal Science.

The researchers — using words, positive tones and plenty of treats, we’d imagine — trained dogs to enter a magnetic resonance imaging machine and lie still while the machine recorded their brain activity.

The methods, similar to those being used at Emory University, are allowing scientists to better understand what goes on in the canine brain.

A trainer spoke common words of praise used by dog owners, including the Hungarian words for “good boy,” “super” and “well done,” as well as neutral words like “however” and “nevertheless.”

All the words were spoken using both positive tones and neutral tones, according to the New York Times.

Only words of praise spoken in a positive tone provoked significant reactions, making the reward centers in a dog’s brain light up.

The researchers at Eötvös Loránd University in Budapest recruited 13 family dogs for the study, and trained them to sit totally still for seven minutes in an fMRI scanner. The dogs were not restrained, and “could leave the scanner at any time,” the authors said.

Using the brain activity images, the researchers saw that the dogs processed the familiar words regardless of intonation, and they did so using the left hemisphere, just like humans. Tone, on the other hand, was analyzed in the auditory regions of the right hemisphere.

Using neutral words in a positive tone, or positive words in a neutral tone, produced little reaction — or at least not one that shows up in MRI machines.

“It shows that for dogs a nice praise can very well work as a reward, but it works best if both words and intonation match,” Andics said. “So dogs not only tell apart what we say and how we say it, but they can also combine the two, for a correct interpretation of what those words really meant.”
(Photos by Enik Kubinya, via New York Times)

A study at Emory University suggests that dogs aren’t strictly the food-obsessed beasts they’ve traditionally been seen as — and that many, maybe even most, prefer attention and praise over a chewy treat.

While only 13 dogs participated in the study, there were only two of them who — judging from their neural reactions — showed a distinct preference for food over praise.

The study, published in the journal Social, Cognitive and Affective Neuroscience, is one of the first to combine brain-imaging data with behavioral experiments to explore what kind of rewards canines prefer.

“We are trying to understand the basis of the dog-human bond and whether it’s mainly about food, or about the relationship itself,” says Gregory Berns, a neuroscientist at Emory and lead author of the research.

“Out of the 13 dogs that completed the study, we found that most of them either preferred praise from their owners over food, or they appeared to like both equally. Only two of the dogs were real chowhounds, showing a strong preference for the food.”

Berns heads the Dog Project in Emory’s Department of Psychology. It was the first to train dogs to voluntarily enter a functional magnetic resonance imaging (fMRI) scanner and remain motionless during scanning, without restraint or sedation.

Their previous research using the technique identified the ventral caudate region of the canine brain as a reward center and showed that region responds more strongly to the scents of familiar humans than to the scents of other humans, or even to those of familiar dogs.

Phys.org reports that, in the new study, researchers trained the dogs to associate three different objects with different outcomes. A pink toy truck signaled a food reward; a blue toy knight signaled verbal praise from the owner; and a hairbrush signaled no reward, to serve as a control.

The dogs then were tested on the three objects while in an fMRI machine. Each dog underwent 32 trials for each of the three objects as their neural activity was recorded.

Four of the dogs showed a particularly strong activation for the stimulus that signaled praise from their owners. Nine of the dogs showed similar neural activation for both the praise stimulus and the food stimulus. And two of the dogs consistently showed more activation when shown the stimulus for food.

Berns says the findings run counter to the old view that dogs “just want food and their owners are simply the means to get it … Another, more current, view of their behavior is that dogs value human contact in and of itself.”

In another part of the study, dogs were put into a Y-shaped maze in which one path led to a bowl of food and the other path to the dog’s owner.

The dogs were repeatedly released into the room and allowed to choose one of the paths.

While most dogs alternated between the food and their owner, dogs who showed a greater response to praise in the first part of experiment chose to go to their owners 80 to 90 percent of the time.

Berns said the study “shows the importance of social reward and praise to dogs. It may be analogous to how we humans feel when someone praises us.”

(Photos: At top, Kady, a Lab-retriever mix in the study who preferred praise from her owner to food; at bottom, Ozzie, a shorthaired terrier mix who chose food over his owner’s praise / Emory University)

If you’re wondering how your dog is able to magically sense when you are sad, take a look in the mirror.

(And quit moping, you might be bringing your dog down.)

A new study suggests dogs have a specialized region in their brains for processing faces, and that face-reading region in the temporal cortex may help explain how they’ve become so adept at reading human social cues — a skill that up to now has, at least in the eyes of scientists, only been well-documented in humans and other primates.

Dogs have “neural machinery” that has been “hard-wired through cognitive evolution,” says Gregory Berns, a neuroscientist at Emory University and the senior author of the study.

Berns heads the Dog Project in Emory’s Department of Psychology, which is researching evolutionary questions surrounding man’s best friend.

The project was the first to train dogs to voluntarily enter a functional magnetic resonance imaging (fMRI) scanner and remain motionless during scanning, without restraint or sedation.

In previous research, the Dog Project identified a region of the canine brain that served as a reward center, and showed that region was responsible for a dog’s brain responding more strongly to the scents of familiar humans than to the scents of other humans, or even to those of familiar dogs.

In the current study, the researchers focused on how dogs respond to faces versus everyday objects, reports Phys.org.

“Dogs are obviously highly social animals,” Berns says, “so it makes sense that they would respond to faces. We wanted to know whether that response is learned or innate.”

The answer appears to be it’s a little of both — it was there to begin with, but has been honed over centuries of socializing with humans.

The study involved dogs viewing both static images and video images on a screen while undergoing an MRI.

Since dogs do not normally interact with two-dimensional images, they had to undergo training to learn to pay attention to the screen. Only six of the eight dogs enrolled in the study were able to hold a gaze for at least 30 seconds on each of the images, but for each of those six a region in their temporal lobe responded significantly more to movies of human faces.

The researchers have dubbed the canine face-processing region they identified the dog face area, or DFA.

(We assume they came up with that using that area of the human brain that is not too imaginative and wants to give everything an acronym.)

A previous study, decades ago, using electrophysiology, found sheep had facial recognition skills, but only a few face-selective cells were identified, as opposed to an entire region of the cortex, said Daniel Dilks, an Emory assistant professor of psychology and author of the study.

Humans, by the way, have at least three face processing regions in the brain.

“Dogs have been cohabitating with humans for longer than any other animal,” Dilks said. “They are incredibly social, not just with other members of their pack, but across species. Understanding more about canine cognition and perception may tell us more about social cognition and perception in general.”

A neuroscientist who has been spent two years trying to scan images of their brains says dogs seem to have feelings and emotions, not unlike those of a human child.

Gregory Berns, a professor of neuroeconomics at Emory University, has been able to scan the brains of a dozen dogs using an M.R.I, which is quite an achievement in itself. But in looking at those scans he says he has reached the conclusion that, “Dogs are people, too.”

“The ability to experience positive emotions, like love and attachment, would mean that dogs have a level of sentience comparable to that of a human child,” he wrote in an op-ed piece that appeared in Saturday’s New York Times. “And this ability suggests a rethinking of how we treat dogs.”

Bern set out to determine how dogs’ brains work, and what they might be thinking. To that end, he began training dogs to undergo — and stay still during — M.R.I. scans, willingly and while awake and unrestrained.

“Conventional veterinary practice says you have to anesthetize animals so they don’t move during a scan. But you can’t study brain function in an anesthetized animal,” he notes. “At least not anything interesting like perception or emotion.”

Initially, he worked with his own dog, Callie, a black terrier mix he adopted from a shelter, using a simulated M.R.I. he built in his living room. As word spread about his research, others volunteered their pets and Berns soon had a dozen dogs “M.R.I.-certified.”

“After months of training and some trial-and-error at the real M.R.I. scanner, we were rewarded with the first maps of brain activity. For our first tests, we measured Callie’s brain response to two hand signals in the scanner. In later experiments, not yet published, we determined which parts of her brain distinguished the scents of familiar and unfamiliar dogs and humans.”

Berns and his team focused on a key brain region called the caudate nucleus, which sits between the brainstem and the cortex. In humans, the caudate, rich in dopamine receptors, plays a key role in the anticipation of things we enjoy, like food, love and money. Same with dogs — except, we’re pretty sure, for the money part.

“Specific parts of the caudate stand out for their consistent activation to many things that humans enjoy,” he says. “Caudate activation is so consistent that under the right circumstances, it can predict our preferences for food, music and even beauty … In dogs, we found that activity in the caudate increased in response to hand signals indicating food. The caudate also activated to the smells of familiar humans. And in preliminary tests, it activated to the return of an owner who had momentarily stepped out of view.”

Berns believes the scans will tell us more than behavioral observations do about what dogs are thinking.

“Do these findings prove that dogs love us? Not quite,” Berns wrote. “But many of the same things that activate the human caudate, which are associated with positive emotions, also activate the dog caudate.”

That “functional homology,” as neuroscientists call it, may be an indication of canine emotions.

And given that, he asks, is it time to stop considering them property and start affording them some rights as individuals?

“If we went a step further and granted dogs rights of personhood, they would be afforded additional protection against exploitation,” he says. “Puppy mills, laboratory dogs and dog racing would be banned for violating the basic right of self-determination of a person.”

That day may not be directly around the corner, he notes, but with more being learned about how their brains work, and what thoughts run through them, it could eventually arrive.

“Perhaps someday,” he says, “we may see a case arguing for a dog’s rights based on brain-imaging findings.”

With all the research into how the medical issues of dogs often run parallel to our own, it’s no surprise that eight obsessive-compulsive Doberman pinschers are adding to our body of knowledge about that disorder.

A new study made use of MRI brain scans and found dogs and people with obsessive compulsive disorder (OCD) have similar brain abnormalities and share certain brain characteristics.

Three years ago, researchers found the shared gene believed responsible for flank-sucking, blanket-sucking and other compulsive behavior in Dobermans.

The new study shows what’s going on in their brains is similar — at least as an MRI sees it — to what’s going on in our’s.

“We have a lot of commonality with our best friend the dog,” said study leader Niwako Ogata, an assistant professor of animal behavior at Purdue University College of Veterinary Medicine in Indiana.

Just as elderly dogs with the canine equivalent of Alzheimer’s are being used as models to understand the degenerative disease in people, studying dogs is providing some clues into OCD, an anxiety disorder afflicting anywhere from 2 to 8 percent of Americans.

For the study, Ogata and colleagues recruited eight Doberman pinschers with CCD (canine compulsive disorder) and a control group of eight Dobermans without CCD, according to National Geographic. The team obtained MRI scans for each group and discovered that the CCD dogs had higher total brain and gray matter volumes and lower gray matter densities in certain parts of the brain. That’s similar to the structures of people brains’ with OCD.

It’s not known why both species’ brains show these features, Ogata said, but her team plans to repeat the experiment with more dogs and more breeds.

The team chose Dobermans because of the prevalence of CCD in the breed. About 28 percent of Dobermans in the U.S. are afflicted.

People with OCD often perform the same rituals over and over again, like washing and rewashing their hands and locking and relocking doors. In dogs, common compulsive behaviors include paw-licking and tail-chasing.

Ogata, whose study was published online in April in the journal Progress in Neuro-Psychopharmacology & Biological Psychiatry, said the study provides a better idea of “”how brains develop, and when and how genes interact with [their] environment to cause some behavior problems for both humans and dogs.”